The long term mission of this Center is to develop and test a safe, effective, reversible contraceptive vaccine. Emphasis will be placed upon, but not limited to, a vaccine for females. The vaccine will consist of one or several gamete associated immunogens which elicit immunological responses that function to prevent fertilization. The Center will coordinate research and development activities encompassing seven stages of a recombinant contraceptive vaccine product development program: 1) Fundamental discovery and evaluation of gamete specific molecules [vaccinogens] derived from the sperm, egg, egg investments or accessory reproductive organs; 2) Genetic engineering of genes encoding specific vaccinogens into appropriate expression systems; 3) Production and purification of recombinant vaccinogens under good laboratory practices; Formulation of vaccine doses; 4) Small animal and primate testing of vaccine formulations for immunogenicity, safety and efficacy; 5) Evaluation of mechanisms of vaccine action; 6) Human trials in association with industrial sponsorship; 7) Development of diagnostics to monitor infertility status. Four research projects will be initiated in the first year: 1) Evaluation of peptides derived from ZP3 [Tung]; 2) Identification and cloning of a new human sperm surface antigen which functions in sperm/zona binding [O'Rand]; 3) Cloning and characterization of a human sperm antigen identified with infertile sera [Goldberg]; and 4) Development and testing of a oral sperm vaccine for stimulating secretory immunity in the oviduct [Herr]. Already existing grants concerned with primate efficacy trials of injectable contraceptive vaccines based upon human sperm immunogens LDH-X and SP-10 will be incorporated into the Center and expanded into reversibility and phase I human trials, if successful ongoing efficacy studies warrant. Attention will be placed on development of multideterminant vaccine [combination] formulations if indicated. Core resources will be developed in the following areas: tissue specificity, bioprocess and product development, immunopathology, oral vaccine vectors, animal models, clinical studies/regulatory affairs and administration, including a postdoctoral training component. Existing cores performing services in contemporary cell and molecular biology at several institutions will be marshalled in support of the Center. A multi-institutional, interdisciplinary group of principal investigators with solid experience in the discovery and evaluation of candidate contraceptive vaccine immunogens is assembled. An industrial sponsor will provide conceptual and financial support to the program in the areas of regulatory affairs, preclinical and clinical trials. The Center is overseen by an Executive Committee representing industry, the FDA, immunology, and obstetrics and gynecology.